.row
  .col-md-6.col-md-offset-3.sign-in
    = f_form_for @product, html: { multipart: true } do |f|
      = f.error_messages
      = f.text_field :name
      = f.price_field :price
      = f.collection_select :category, Product.categories.keys
      = f.number_field :stock
      = f.number_field :calories
      = f.file_field :avatar
      = f.submit